With the development of network environments in recent years, user authentication is required of users in various situations. Typically, user authentication is required in cases where on-line services such as on-line shopping or email services are provided; and in addition, user authentication is required from the viewpoint of internal administration in such a case in which accessible information is restricted for each department even on a closed network such as an enterprise network.
User authentication requires a user ID and a password (login information) to be input; however, in recent years, in order to improve the convenience (usability) for users, a mechanism for automatically inputting login information has been developed (for example, Patent Document 1).
There are various methods of implementing a mechanism for automatically inputting login information, such as, for example, a method in which login information is stored in a browser of a user terminal, and the login information is automatically input inside the user terminal, and a method in which login information is stored in an administrative server on a network, and based on a request (involving cookie information) from a user terminal, a web page, into which the login information has been automatically input, is displayed on the user terminal.    Patent Document 1: Japanese Unexamined Patent Application, Publication No. 2004-295252